class_docstr: Data structure to store a particular path between 2 nodes.
docstr: path is a list
docstr_tok: ["path","is","a","list"]
code: def update(self, path, is_blocked):
      """
      path is a list
      """
      self._is_blocked = is_blocked
      if not is_blocked:
          self._condition_vars = self._condition_vars.union(
              set(path[1:-1])
          )
  
imports: import networkx
  from dowhy.utils.graph_operations import adjacency_matrix_to_adjacency_list
label_desc: Use image node_id 2 for calling the Path obj's underlying member method code with example usage: obj.update(path, is_blocked) without return types